Incandescent-lamp fixture.



w. c. H. WEFEL INCANDESCENT LAMP FIXTURE.

APPLICATION FILED DEC-14.19M-

Patented Feb. 19, 1918.

INVENTOR. IVC. H flsFcL.

U TEE rte.

INGANDESCENT-LAMP FIXTURE.

Specification of Letters Patent.

Patented Feb. 19, 1918.

Application filed December 14, 1916. Serial No. 136,969.

To all whom it may concern:

Be it known that 1, WILLIAM GHJVEFEL, a citizen of the United States, residing at Denver, in the county of Denver and State of Colorado, have invented certain new and useful Improvements in Incandescent-Lamp Fixtures, of which the following is a specification.

This invention relates to incandescent lamp fixtures and its object is to provide a fixture which in combination with a socket for connecting an incandescent lamp in an electric circuit, include means to complete the circuit around the socket and to automatically include therein a resistance equivalent to that ordinarily produced by the lamp, in case the filament of the lamp is broken or the path of the current through the socket is otherwise interrupted.

My improved fixture is particularly designed for use in a circuit in which a number of lamps are connected in series, it being observed that by virtue of the distinctive properties hereinabove described, it insures in case of breakage of one of the lamps included in the circuit, a continued flow of current through the other lamps and thus prevents the extinguishment of all the lamps in series in a circuit by the incapacitation of one.

My improved fixture is furthermore especially adapted for use on street cars which by reason of the high voltage direct current circuit employed for their propulsion must, if lighted by electricity from the same source necessarily include a lighting circuit in which the lamps are placed in series.

It is at present customary to equip each street-car with two or more independent lighting circuits so that if the lamps in one circuit are extinguished by the breaking 0 one, the lamps in the other circuits will prevent the car from being entirely destitute of light.

By the use of my invention, incandescent lamps of a car if placed in series in a direct current lighting circuit of high voltage, may be used to the same advantage as those connected in multiple in an alternating current circuit, inasmuch as the extinguishment of one lamp will not aifect the others.

An illustrative embodiment of my invention has been shown in the accompanying drawings in the various views of which like parts are similarly designated, and in which- Figure 1 is a sectional view of a series incandescent lamp-fixture made in accordance with my invention,

Fig. 2, a section taken along -22, Fig. 1, and

Fig. 3, a sectional elevation of a modification of my invention illustrating its adaptation to a use other than that for which it is principally designed.

In the drawings the reference numeral 3 designates a base of nonconductive material upon which all the cooperative elements of my improved fixture are assembled, and l.- an escutcheon which covers the parts on the base and i designed to lend an artistic and finished appearance to the completed article.

The base is preferably circular and is provided with holes 5 for the reception of screws by which it is fastened against a car ceiling or other surface and with an opening 6 for the passage of a conductor of a circuit in which the fixture of which it forms part, is connected.

Secured axially in the center of the base i an incandescent lamp socket 7 of conventional construction including a screwbeaded shell 8 into which the lamp 9 is inserted as usual, and a pair of insulated binding screws 10 by which the conductive parts of the socket are connected in the circuit.

The base furthermore supports a pair of resistance coils 12 connected in series by a wire 13, and a switch including an adjustable stationary contact-member and a relatively movable contact member which consists of the pivoted and spring-controlled armature of an electro-magnet.

The stationary contact member consists of a conductive plate 13 rigidly secured to the base and provided with a binding-screw 14, and a blade 15 which is pivotally connected with the plate by means of a screw 16.

The electro-magnet of which the movable contact-member is a part, comprises a coil 17 which is fastened upon the base by screws 18 and an armature 19 placed alongside the coil and pivoted upon a stud 20 on the base.

The pivoted armature carries at one of its ends a contact plate 21 adapted to engage the end of the blade 15, and its opposite end the line is connected with a post 22 on the base, by means of a coil spring 23 which tends to move the contact end of the armature into engagement with the blade of the stationary contact-member of the switch.

The connection and the spring 23 is established through the intermediary of a screw 21 and a nut 25 which permit of varying the tension of the spring to any desired degree.

The conductor by which the fixture is connected in an'electr-ic circuit designated by the lines 30 and 31, is broken for the inclusion of the socket in the circuit, its two sections having been designated in Fig. 2 of the drawings by the reference numerals 26 and 27 which pass through the opening 6 of the base and connect with the binding screws 10 of the socket 7.

The windings of the electro-magnetic switch are connected in series with the socket 7, in the conductor section 26 and the sta tionary contact-member 15 is connected in the same section by means of the binding screw 14.

The resistance coils 12 are connected in series in a shunt 28 of the conductor in which the socket is connected, one end of the shunt connecting with the section 27 of the conductor through the medium of a binding post 29, and the other end of the same connecting with the armature 19 of the electro-magnetic switch, the last-mentioned connection being flexible to permit of the movement of the armature about its pivotal axis.

The escutcheon which incloses the operative parts of the fixture, consists of a concave cup 32 of thin metal the circular edge of which engages the marginal portion of the base 3,

The escutcheon has a central opening 34 to admit the plug of an incandescent lamp 9 screwed into the shell 8 of the'socket 7 and it is furthermore provided with one or more series of vent-holes 35 for the circulation of air to prevent the accumulation of heat when the resistance coils are in circuit.

The escutcheon is secured in place on the base by means of a nut 36 which is screwed upon the exterior of the socket shell8 and which has at its outer end a flange which engages the rim, of the escutcheon around its central opening 3%.

In the use of my improved fixture, the filament 37 of a lamp 9 inserted in the socket incandesces by a fiow of current along a path which commencing with the source of electricity 37, includes the positive line wire 31, the part 27 of the broken conductor in which the socket is connected, the filament of the lamp 9, the other part 26 of the conduetor in which the electro-magnet coil 17 is included and the negative line wire 30 which connects with the other pole of the source of electricity.

between the armature 19 1 otherwise rendered defective,

It will thus be seen that when the lampfilament is in its normal incandescent condition, the electro-magnet is energized and by its attractive force holds the armature 19 in a position in which its contact plate is separatedfrom the blade 15 of the stationary contact member against the action of the spring 23.

When the filament breaks or the lamp is the magnet which is in series with the socket is simultaneously deenergized with the result that its armature is moved into engagement with the stationary contact-member 15 by the spring 23.

The current instead of passing through the socket now flows from the conductor section 27 which connects with the line-wire 31 through the shunt 28 in which the resistance coils are connected, and by means of the contacting pa ductive member 26 which connects with the line-wire 30. V

The ohmic resistance of the coils 12 slightly exceeds that ordinarily afforded by rts l9 and 15., through the con' the lamp filament, so that after the circuit is broken in the socket and completed around the same by the automatic action of the electro-magnetic switch, the flow of current through the other lamps of the series remains unchanged and the lamps will continue to. incandesce as before.

It will thus be seen that every benefit derived from an alternating current circuit of 110 volts in which lamps are placed in multiple, are by the use of my improved fixture obtained in a direct current circuit of higher voltage in which the lamps are necessarily connected in series. Y

It will furthermore be observed that by merely removing the nut 36 which secures the escutcheon, all the parts of the fixture are rendered accessible for adjustment, replacement, or repairs, that by adjustment of the movable contact-member 15 and the spring 23 the sensitiveness of the electromagneticvswitch can be varied to any desired degree, and that the arrangement of the operative-parts of the fixture permit of the use of standard material throughout.

The escutcheon 4 may be provided with a socket 42 as shown in Fig. 1 of the drawings, for the attachment of a lamp-shade or reflector.

In Fig. 3 of the drawings, the fixture is secured at the end of a socket 38 which per- I desire it understood that other variations in the arrangement of the parts of my series incandescent lamp-fixture, as shown in the drawings and above described, may be made means to adapt it for use in other places in which the connection of incandescent lamps in series is required.

Having thus described my I claim and desire to secure ent is:

1. A canopy incandescent lamp fixture comprising a base having means for securing the fixture in an operative position, an incandescent lamp-socket projecting from the base, a canopy forming in cooperation with the base, a chamber around the socket, a conductor in which the ocket is connected, an electro-magnetic switch in said chamber, connected in said conductor in series with the socket, a shunt of said conductor controlled by the switch, and a resistance-coil in said chamber, connected in said shunt.

2. A canopy incandescent lamp fixture comprising a base having means for securing the fixture in an operative position, an

invention what by Letters-Patincandescent lamp-socket projecting from the base, anut on said socket, a canopy supported on said nut and forming in cooperation with the base, a chamber around the socket, a conductor in which the socket is connected, an electro-magnetic switch in said chamber, connected in said conductor in series with the socket, a shunt of said conductor controlled by the switch, and a resistance coil in said chamber, connected in said shunt.

3. A canopy incandescent lamp-fixture comprising a base having means for securing the fixture in an operative position, an incandescent lamp-socket projecting from Copies of this patent may be obtained for five cents each, by addressing the the base, a canopy forming in cooperation with the base, a chamber around the socket, a conductor in which the socket is connected, an electro-magnetic switch in said chamber, connected in said conductor in series with the socket, and composed of an electro-magnet, and an adjustable contact disposed to be engaged by the armature thereof when the magnet is deenergized, a shunt of said conductor controlled by the switch, and a resistance-coil in said chamber, connected in said shunt.

l. A canopy incandescent lamp-fixture comprising a base having means for securing the fixture in an operative position, an incandescent-lamp socket projecting from the base, a canopy forming in cooperation with the base, a chamber around the socket, a conductor in which the socket is connected, an electro-magnetic switch in said chamber, connected in said conductor in series with the socket, and composed of an electro-magnet, 21 contact disposed to be engaged by the armature thereof when the magnet is deenergized, and an adjustable spring to move the armature toward the contact, a shunt of said conductor controlled by the switch, and a resistance-coil in said chamber, connected in said shunt.

In testimony whereof I have affixed my signature in presence of two witnesses.

WILLIAM C. H. WEFEL. lVitnesses:

G. J. ROLLANDET, L. RHoADEs.

Commissioner of Patents,

Washington, D. C. 

